Manual measurement of a work amount of a work machine such as an excavator is a burden on an operator or the like and is troublesome, and thus, automation thereof has been proposed.
On the other hand, manually-measured or automatically-measured work amount is preferably used for management. Accordingly, in Patent Literature 1, the number of times of loading is measured by operation of a count switch which operation is performed by an operator and the measured accumulated number of times of loading in one day is displayed on a monitor of an excavator.